xfrm: Introduce LINUX_MIB_XFRMFWDHDRERROR

XFRMINHDRERROR counter is ambigous when validating forwarding
path. It makes it tricky to debug when you have both in and fwd
validation.
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/snmp.h

@@ -257,6 +257,7 @@ enum
 	LINUX_MIB_XFRMOUTPOLBLOCK,		/* XfrmOutPolBlock */
 	LINUX_MIB_XFRMOUTPOLDEAD,		/* XfrmOutPolDead */
 	LINUX_MIB_XFRMOUTPOLERROR,		/* XfrmOutPolError */
+	LINUX_MIB_XFRMFWDHDRERROR,		/* XfrmFwdHdrError*/
 	__LINUX_MIB_XFRMMAX
 };
 

net/xfrm/xfrm_policy.c

@@ -2045,8 +2045,7 @@ int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 	int res;
 
 	if (xfrm_decode_session(skb, &fl, family) < 0) {
-		/* XXX: we should have something like FWDHDRERROR here. */
-		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
 		return 0;
 	}
 

net/xfrm/xfrm_proc.c

@@ -41,6 +41,7 @@ static const struct snmp_mib xfrm_mib_list[] = {
 	SNMP_MIB_ITEM("XfrmOutPolBlock", LINUX_MIB_XFRMOUTPOLBLOCK),
 	SNMP_MIB_ITEM("XfrmOutPolDead", LINUX_MIB_XFRMOUTPOLDEAD),
 	SNMP_MIB_ITEM("XfrmOutPolError", LINUX_MIB_XFRMOUTPOLERROR),
+	SNMP_MIB_ITEM("XfrmFwdHdrError", LINUX_MIB_XFRMFWDHDRERROR),
 	SNMP_MIB_SENTINEL
 };